Protein plastic molding compound and method of preparing the same



Patented Novrll, 1941 x rno'rnm PLASTIC Momma COMPOUND ANDMETHOD or PREPABINGTHESAME George H, Brother, Urbana, Leonard L.

McKinney, Champ aign, 111., asalgnors to Henry A. Wallace, as- Secretary United States oi. America of Agriculture the No Drawing. Application July 8, 193a,

Serial lilo. 2111.120

20mm. (01. zoo-'1) I (Granted under the act of March a, 1883, as

This application is made under the act of March 3, 1883, as amended by the act of April 30, 1928, and the invention herein described and claimed, it patented, may be manufactured and butwe do not wish to limit our invention to them. They may be used in any proportion with the amended April 30, 1928; 370 0. G. 75'!) the specific purposes of this invention, the resin or resinous material should not exceed 49 percent of the mixture. The molding operation is performed with the mixture of the thermoplastic thermoplastic hardened protein material, but for 55 used by or for the Government of the United .hardened protein material and the resin or res- States of America ifor governmental purposes, inous material by methods well known to thosewithout the payment to us of-any royalty thereon. skilled in the art. If the resin used is a phenolic- One object of our invention is the production or a urea-formaldehyde, the mixture will be of a new and superior protein plastic molding found to have thermosettlng properties and can material consisting essentially of thermoplastic be removed from the hot die without chilling hardened protein material and a compatible under pressure. resin. It has long been known to those skilled in the Another object of our invention is the producrt that pro ein Pl tic ma rial possesses ood tion of a new and superior low priced molding stre th and toughness. Inor r oimpflrt hese material consisting principally of thermoplastic desirable qualities to resinous materials, numerhardened fat-free soybean meal mixed with a a 11 m x s av n P p d in WhiCh'nOn- 'compatible resinous material, hardened protein material has been added to These objects'are attained by first preparing modify the character of the resinous material. the thermoplastic hardened protein material. As e p s we te e fo lowin Essentially this consists in treating the protein M M or protein material for 12-16 hours at room tem- U. Pm m m 33 g 651mm perature with an aldehyde, such as formaldegag. gag. 1 June 18,1901 g1 g1 013: 131 hyde, in water solution adjusted to a pH within g I 3 m2 the isoelectric range of the protein; or the pro- G2}. PatI. 316? 32. 2111913. fifi'ifi Berend tein material may be mixed dry with a slight ex- Kgggtg'g 1 22,1916 W w pt. 12,1919 T.I\akan1shi cess of formaldehyde adlusted to the proper pH. gag. gag. 1 1741,5 0 N 1 HH. 1 2 011 l- 1 The residue from the extraction of protein mm Pu. 2 g; 24,1922 Hum gfg aldehyde, especially formaldehyde, solutions, may grit. gag. 122,32; })ec. 0. 1 1111). ng. a e: also be used. This material in the case of a Kf' g 3 1 ,gg;g,';. g seed meal, such as fat-free soybean meal, would gr. Pat. 024 i p %1 =s 1 st contain 30 to 40 percent formaldehyde hardened 3: :38 29:211 i 2221928 ag; protein and, as a. by-product from the protein 5:. gag. 31 1:. 15.1 3: I. o F i rbitAkt. Ges. extraction process, would be very inexpensive. F The protein materialis dried at c. (71 F.) to 's. 13%: 2.318% afpt. 8,1936 3:355:11

. Otllcrproteim with phenol-formaldehyde v r. Pt. ass Jul 1,1931 12.011 i i gufil- Ufa-r31. 1,%3475 Jan? 22,1935 H. Bglfil l z n. 8.1at. ,131 July 19,1910 .8. B. Goldsmith z U. 5. Pat. 2,041,901 July 21, p. w. 11m SoybeflL U. 8. Pat. 2,006,736 July 2,1935 L. J. Fuhrmann Albumim U. 8. Pat. l,0m,l88 Dee. 2.1913 F. G. Wiechmann Albmnim U. s. Pat. 1,076,417 Oct. 21,1913 B. B. Goldsmith omen. U. s. Pat. 952,724 Mar. 22,1910 L. Berend 91 Fr. Pat. 751,798 ,Sept. 9,1933 Laurlnand Bidot 01m, U. s. Pat. 11mm Aug. 14,1934 Laurin and Bidot a moisture content of not over 5percent. The 0min I W dried hardened protein material, which has been Fr. Pat- 6,21o June 18,192! r. Schmidt :gownito be tliiermoplatstiialis tlifn mixted wliith 5 g2: 11:? fzfi 5 2a gfi Tfifii eresnor res nous ma era,s11c as'ap eno can nover $89, urea-forigaldehydiihresin or1 ai1 reisli iious1 mgldg5: g; z gjfi gas: 2%: g -hkfigg compoun,orw apoyy cac'ooe 0 polycarboxylic acid resin, by any suitable means, 3; S: 1 i111; m l f j l t in such as togetherjn a min or 50 Ft. PM. 788,407 Oct. 10,1935 Gl'll ville and DBVIOH case of the phenolics, compounding on calendar 3; 212:: 23%;;32 31% 8:33: gt}: rolls. The resins specified above are preferred, U 210901452 "11937 Hawker process, described by Herbert Chase in British 1936, in which soybean meal is mixed with wood flour, phenol, formaldehyde, lime, etc., to produce a molding material. In this, as in all the other cases listed, the protein material is not hardened when introduced into the mixture and such hardening as may take place in the mixture is not controlled within the pH ranges where we have found the thermoplastic hardened protein material to be produced which we specify and which we have found to be much superior for plastic purposes.

Our invention differs from all these and others to be found in the literature in the fact that we have discovered a new protein plastic, modified by mixing resins or resinous materials with thermoplastic hardened protein material of reduced water content. In all previous work, the unhardened protein was added to modify the resinous molding material. In consequence, the

, amount of protein material was considerably less with an aldehyde within the proper pH range and dried to under 5 percent moisture content. All mixing of the thermoplastic hardened protein material with the resinous material was done by grinding together in a ball or pebble mill for 12 to 16 hours.

In'order to illustrate our invention, the following specific examples are set forth:

Example 1.75 parts thermoplastic formaldehyde-hardened soybean alpha protein mixed with 25 parts phenolic molding compound (Bakelite BM 120) and 1 part aluminum tristearate. Molded at 330 F. (165 C.) at a pressure of 2,000 to 4,000 pounds per square inch for 3 minutes in the heated die and removed without chilling the die. Water absorption, 11.5 percent.

Example 2.5Q parts thermoplastic io'rmaldehyde-hardened soybean alpha protein mixed with 50 parts phenolic molding resin (Bakelite KM 9131). Molding conditions as in Example 1. Water absorption 4.7 percent.

Example 3.--70 parts thermoplastic formaldehyde-hardened soybean alpha protein mixed with 5 parts ethylene glycol, 1 part aluminum tristearateand 25 parts phenolic molding compound (Bakelite BM 120), Molding conditions as described in Example 1. Water absorption, 15.5

. percent.

In addition, it has thermosetting properties in that it can be removed from the hot die without first chilling under pressure. Such a material will find a wide use in the trade wherever it is desirable to combine beauty with strength and where absolute water resistance is not essential, such as in the manufacture of buttons, beads, combs, interior electrical insulation, etc.

A very inexpensive but good protein molding plastic material may be prepared from a mixture of 25 to 50 percent of a molding compound, such as the phenol-formaldehyde wood flour compound, with thermoplastic formaldehyde hardened fat-free soybean flour. This material is limited to opaque colors and it has a water absorption of about 20 percent, but it is strong and permanent and molds readily, setting'up in the hot die. A small amount of an agent, such as aluminum stearate is recommended in this mixture to increase the water resistance. Such a material will find a wide use in the lower price field in which shellac and other similar molding materials have not been very satisfactory. It may even find some application in the buildin trade, replacing inferior materials used in wall boards, etc. The wood flour may be replaced with thermoplastic hardened soybean meal to advantage.

Having described our invention, we give the following specific examples in illustration of the same, but we do not wish to be limited to these proportions nor to the specific commercial products we mention. All proportions given are parts by weight. Water absorption was determined by the method of A. S. T. M. 13-45-33, which consists in molding test discs 2 inches in diameter by 54; inch. thick, heating these in an oven at 50", (2. (122 F.) for 24 hours to condition, weighin'gFimmersing in distilled water for 24 hours at room temperature, and reweighing, the condiitioned weightbeing taken as the dry weight, All

protein material had been hardened by treatment sorption, 21.5 percent.

Example 4.50 parts thermoplastic formaldehyde-hardened soybean alpha protein mixed with 50 parts urea-formaldehyde molding mixture (Plaskon Ivory 447). Molded at 280 F. (138 C.) at a pressure of 2,000 to 4,000 pounds per square inch for 3 minutes in the heated die and removed without chilling the die. Water absorption, 1.9 percent.

Example 5. parts thermoplastic formaldehyde-hardened fat-free soybean meal mixed with 1 part aluminum tristearate and 25 parts phenolic molding compound (Bakelite BM Molding conditions as described in Example 1. Water ab- Example 6.20 parts thermoplastic formaldehyde-hardened soybean alpha protein mixed with 5- parts ethylene glycol and 75 parts phenolic molding compound (Bakelite BM 120) Molding conditions as described in Example 1. Water absorption, 0.7 percent.

Example 7.20 parts thermoplastic formaldehyde-hardened soybean alpha protein mixed with 5 parts ethylene glycol and 75 parts urea-formaldehyde molding compound (Plaskon Ivory 447). Molding conditions as described in Example 4. Water absorption, 3.7 percent.

Example 8.20 parts thermoplastic formaldehyde -hardened soybean alpha protein mixed with 5 parts ethylene glycol and 75 parts phenolic molding resin (Bakelite KM 9131) Molding conditions as described in Example 1.- Water absorption, 3.2 percent.

Example 9,-40 parts thermoplastic formaldehyde hardened soybean alpha protein mixed with 10 parts ethylene glycol and 50 parts phenolic molding compound (Bakelite BM 120). Molded as described in Example 1. Water absorption, 17

I percent.

ing conditions as described in Example 4. Water absorption, 7 percent.

In every case a strong tough plastic resulted that was permanent, i. e., it neither spontaneously fractured nor did it fracture or check on dryingaiterthewaterabsorptiontest.

Althoughwespeciflcallywishtoclalmasour invention the discovery 01 a new and superiorprotein plastic molding compound, we wish to call attention'to Examples 6, 7, and 8 in which the thermoplastic formaldehyde hardened protein is used to modify the properties or the molding resin. This is new to the art, as never before has thermoplastic hardened protein material been employed in this manner and the products have new and unusual features. In every case the strength of the plastic was improved, and in some cases the homogeneity and appearance as well. The water absorption was well within practical limits.

- water-resistant protein molding powder, com-.

Having thus described our invention, whatwe claim for Patent is: 1

1. An article of manufacture, a thermomtting prising essentially 20 parts thermoplastic formaldehyde-hardened soybean alpha protein that has been mixed with substantially 5 parts or -tein that has been mixed with substantially 5 parts ethylene glycol and'substantially 75 parts or a phenolic molding powder consisting of a mixture 01. a B-stage phenol-formaldehyde resin, wood flour, and a suitable accelerator.

GEORGE n. BROTHER I momma 1.. uoxmm. 

